Brush-lifting device for dynamo-electric machines.



E. MATTMAN. BRUSH LIFTING DEVICE FOR DYNAMO ELECTRIC MACHINES, APPLIOA'IION FILED JUNE 21, 1912,

, 1,089,142 Patented M21113, .1914.

2 SHEETS-SHEET l. '0 U v INVENTOR E. MATTMAN. BRUSH LIFTING DEVICE FOR DYNAMO ELECTRIC MACHINES. APPLICATION FILED JUNE 21, 1912.

1,089,142, Patented Mar.3,'1914.

2 SHEETS-SHEET 2. x k

W' INVENTOR UNITED STATES PATENT curios.

EMIL MATTMAN, OF WILKENSEUBG, PENNSYLVANIA, ASSIG-NOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF FENNSYLVANIA.

BRUSH-LIFTING DEVICE FOR DYNAMO-ELECTRiG .ll'IAGHIN'ES.

Yatcntcd Mare 2?, 5?; 4,

Application filed June 2t, 1912. Serial R0. 'FDEJYZQ.

To all whom it may concern Be it known that I,- EMIL ldA'rrMAN, a

citizen of Switzerland, and a resident of Vtilkinsburg, in the county of iillcgheny and State of Pennsylvania, have invented a new and useful Improvement in Brush-Litting Devices for Dynamo-Electric Machines, of which the following is a specification.

My invention relates to] dynamo-electric machines, and it has for its object to pro vide means for temporarily lifting the brushes of a dynamoelectric machine out of engagement with the commutator cylinder which means shall-be effective and reliable in operation and will not cause breakage of the brushes.

lhe invention is particularly useful in connection with rotary converters and similar synchronous machines which have main and auxiliary field poles and are adaptedto be started by current ,receiyed from an alternating current circuit.

- My invention is illustrated in the accompanying drawings, Figure 1 of which is an end view of a part of a machine constructed in accordance therewith. Fig. is a side and sectional view of a part of the said machine, Fig 3 is an enlarged side view of some of the parts that cooperate with the brush to raise it, and Figs. 4, 5, 6, 7, 8 and 9 are detail views of the parts shown in assembled relation in the preceding figures.

The invention is here shown as employed in connection with a rotary converter having a field frame 1 provided with main and auxiliary polar projections 2 and 3, respectively, and with a recess or seat in its end face for the reception of a two-part rocker ring l. The rocker ring serves as a support for a plurality of regularly spaced laterally and radially extending, brackets 5, that are secured thereto but are insulated therefrom, each of said brackets comprising a bar 6 that extends parallel to, and is spaced a suitable distance from, the commutator cylinder 7 of the machine. Each of the bars 6 carries a plurality of side by side brush holders 8 that are rigidly secured thereto and comprise guides for brushes 9 that bear upon, and are resiliently maintained in engagement with, the commutator cylinder' by means of springs 10.

The inner circumferential face of the rocker ring 4 is provided with a recess for the reception or an outer circumferential boss 11 upon another ring 12, which may be rotated with respect to the rocker ring by means of a lever 13 that is pivoted to the rocker ring and has a slot and pin connection with the inner ring 12. The ring 12 carries a plurality of regularly spaced arms or brackets M respectively adjacent to the brush holder supports, the said brackets being suitably insulated if] m the ring. Each of the brackets l l is provided at its end with an adjustable clamp for a radially extending rod 15 that is provided at its free end with a laterally projecting pin 16. The said pin is embraced by the bifurcated end of an arm 17 that is rigidly attached at its other end to a rod 18 that extends parallel to the brush holder supporting bar 6, and is rotatably mounted in small brackets 19 carried thereby. Secured to the rod 18 at regular intervals are a plurality of resilient substan tially 'Z-shaped clips or arms :20, the free ends of which project toward, and are adjacent to, the respective brushes, and are provided with small pivotally supported pawls 531 that are normally maintained in the positions shown by means of springs The pawls 21 are adapted to engage the teeth of ratchets 23 that are respectively secure-d to the outer ends of the brushes and extend substantially radially therefrom.

In order to raise the brushes out of on gagementwith the commutator cylinder, the operating lever 13 is rotated in a counter clockwise direction, resulting in a cloclrwise rotation of the inner ring 12 and of the radlally extending rods 15, the new position.

of one of the radially extending rods being shown in broken lines in Fig. l. The rods 15 inturn cause rotation of the bifurcated arms 17 and rotation of the resilient pawl carrying arms 20 in a clockwise direction. The pawls 21 are thus brought into engagement with the teeth of the ratchets with the result that the brushes are moved outwardly,

and out of engagement with the commutator cylinder. The resilience of the pawl-carrying arms, and the resilient pivotal mounting of the pawls, insure reliahleand effective engagement of the pawls with the ratchets, and relieve the brushes of undue trans-verse strains, so that there is litt e or no i ibility of breakage thereof, W hen the machine has attained synchronous speed, the operating lever is again moved to the position shown, whereupon the pawls will become disengaged=from the ratchets, and the brushes Will be returned into engagement with the commutator cylinder by means of the springs 10.

I claim as my invention:

-1. A brush-lifting device for dynamo-e1ectric machines comprising a brush holder, a brush supported thereby, a ratchet carried by the brush, a resiliently mounted pawl adapted to engage the ratchet,-and means for actuating the pawl to move the brush in the holder.

2. A brush-lifting device for dynamo-electric machines comprising a brush holder, a Springactuated brush supported thereby and provided With a ratchet, a resilientlymounted pawl, and means for efi'ecting operative engagement of said pawl With said ratchet for moving the brush in the holder.

3. A brush-lifting device for dynamo-elec- 20 tric machines comprising a brush holder, a brush supported thereby, a ratchet carried by the brush, a pawl adapted to en age the ratchet, a resilient arm to which the pawl is pivoted, and means for actuating the said 25 arm to move the brush in the holder.

In testimony whereof, I have hereunto subscribed my name this 17th day of June, 1912.

EMIL MATTMAN. 

